Willem,
I am most impressed by their beauty, that is a very nice grouping with an understated beauty and quality rather than the drippings of gold and ivory seen on other Sumatran weapons...Not that ivory and gold is a bad thing

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I must say since obtaining the Kelling Hall collection I too have the Sumatran bug and will one day start another grouping of these weapons after I fill wants from other cultures first, thanks for sharing.
Maurice,
The markings are interesting and quite rubbed so I am guessing there is some good age to that example I have. I do not know the basis of those blade side markings but they are, although a little more rigid by design, similar to those found on my Sadap. I have seen similar on another Borneo piece too but I guess there was a lot of similar cultural cross overs in times past.
And yes, Willems and your Ladieng would look great together...I doubt he'd break the set though ;-)
Gav